Toothpastes and gel formulations which include speckles are known in the art. Besides providing a pleasing aesthetic effect, the speckles can be used to enhance the cleaning and polishing functions of the dentifrice. The speckles are preferably a different color or shade than the base of the dentifrice so that they are visually perceptible. Some known speckles can be incorporated into transparent or translucent gel dentifrices without causing the gel base to cloud. From a marketing standpoint, it has been found to be desirable to package such speckle containing dentifrices in transparent or translucent containers so that the speckles can be viewed by consumers.
U.S. Pat. Nos. 4,376,762, 4,376,763, 4,440,877, 4,444,570, and 4,663,152 disclose the incorporation of functional agglomerated speckles into dentifrices. The speckles contain water insoluble powdered material and water insoluble, ethanol soluble ethyl cellulose. The powdered material is characterized as the functional bodying agent while the cellulose acts as a binder. The utilization of a binder has several short comings. By way of example, the binder material may dissolve in the toothpaste or gel, thereby causing the speckles to lose their integrity. Further, the addition of the binder increases the time and expense of producing the speckles. The use of an organic binder may also facilitate the growth of bacteria.
Several other patents disclose the incorporation of speckled particles into dentifrices. These patents include: U.S. Pat. Nos. 3,919,409, 3,928,555, 3,929,987, 4,002,732, 4,003,971, 4,069,311, and 4,069,312. In each of these patents an organic binder is utilized to bind the functional component of the speckled particles. As stated above, there are several drawbacks associated with the use of such a binder.
Moreover, existing speckles are not designed to absorb dyes from colored dentifrice formulations into which the speckles are incorporated. It is desirable for the silica particles to absorb dyes so that they will be readily discernible in the dentifrice. Such absorption produces an aesthetically pleasing effect. Heretofore, in order to incorporate colored speckles into a dentifrice, the speckles are typically dyed prior to being mixed into the formulation. This results in increased manufacturing time and cost.